CyberSecBulletin
CVE-2022-3569NVD status: Modified

Zimbra Collaboration Suite (ZCS): Privilege Dropping / Lowering Errors

Published Updated By the CyberSecBulletin desk

CVE-2022-3569 is a high-severity privilege dropping / lowering errors vulnerability in Zimbra Collaboration Suite (ZCS) from Synacor, with a CVSS 3.1 base score of 7.8 out of 10. It can be exploited with local access to the system by an attacker with a low-privileged account, without any action from a user. Affected Zimbra Collaboration Suite (ZCS) versions: 9.0.0 and earlier. The record does not name a fixed version, so check the vendor advisory. There is no confirmed exploitation so far. EPSS estimates a 0.77% chance of exploitation within 30 days, higher than 56% of scored CVEs.

Next patch cycle

High severity with no evidence of exploitation so far.

What to do

  1. Check which version of Zimbra Collaboration Suite (ZCS) you run against the affected versions below, and install the vendor's latest release.

Affected products and versions

VendorProductAffected versionsFixed in
SynacorZimbra Collaboration Suite (ZCS)9.0.0 and earlierNot stated
SynacorZimbra Collaboration Suite9.0.0 and earlierNot stated

Version data comes from the organisation that assigned the CVE. Confirm against the vendor advisory before deciding you are unaffected.

How the severity score breaks down

Attack vector
LocalThe attacker needs local access or must trick a user into running something.
Attack complexity
LowNo special conditions are needed; the attack works reliably.
Privileges required
LowA basic user account is enough.
User interaction
NoneNo action by a victim is required.
Scope
UnchangedImpact stays within the vulnerable component.
Confidentiality
HighAll data handled by the component can be read.
Integrity
HighData or code can be modified at will.
Availability
HighThe component can be taken down completely.

Vector: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H. Scored by NVD.

Scoring systemScoreSeverityScored by
CVSS 3.17.8HighNVD
CVSS 3.17.8HighCISA (ADP)

Official description

Due to an issue with incorrect sudo permissions, Zimbra Collaboration Suite (ZCS) suffers from a local privilege escalation issue in versions 9.0.0 and prior, where the 'zimbra' user can effectively coerce postfix into running arbitrary commands as 'root'.

Source: the CVE record as published by its numbering authority, via NVD and CVE.org.

The underlying weakness: Privilege Dropping / Lowering Errors

The product does not drop privileges before passing control of a resource to an actor that does not have those privileges.

How developers prevent this class of flaw

  • Compartmentalize the system to have safe areas where trust boundaries can be unambiguously drawn. Do not allow sensitive data to go outside of the trust boundary and always be careful when interfacing with a compartment outside of the safe area. Ensure that appropriate compartmentalization is built into the system design, and the compartmentalization allows for and reinforces privilege separation functionality. Architects and designers should rely on the principle of least privilege to decide the appropriate time to use privileges and the time to drop privileges.
  • Very carefully manage the setting, management, and handling of privileges. Explicitly manage trust zones in the software.
  • Consider following the principle of separation of privilege. Require multiple conditions to be met before permitting access to a system resource.

More Privilege Dropping / Lowering Errors vulnerabilities (CWE-271)

Timeline

  1. CVE record published.
  2. CISA published its SSVC assessment (exploitation: poc, automatable: no, technical impact: total).
  3. Record last changed materially (score, affected products, status or references).

References

Patches and release notes

Third-party and government advisories

Technical write-ups (may include proof of concept)

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